>their entire army was cavalry, This isn't really true. They also had a fairly advanced siege corps, utilizing cannons and bombs to take down fortifications.

>their entire army was cavalry, This isn't really true. They also had a fairly advanced siege corps, utilizing cannons and bombs to take down fortifications. This played a huge role in their ability to conquer. The domination of horse archers was nothing new but traditionally you could hide behind walls and starve them out. Feeding ten thousand besieging troops is hard enough without thirty thousand horses. With the Mongols able to destroy walls, armies needed to fight the pitched battles that horse archers excel at.